Crosslinking neat ultrathin films and nanofibres of pH-responsive poly(acrylic acid) by UV radiation
RIS ID
33739
Abstract
Electrospun polyelectrolyte hydrogel nanofibres are being developed for many applications including artificial muscles, scaffolds for tissue engineering, wound dressings and controlled drug release. For electrospun polyelectrolytes, a post-spinning crosslinking process is necessary for producing a hydrogel. Typically, radiation or thermal crosslinking routines are employed that require multifunctional crosslinking molecules and crosslink reaction initiators (free radical producers). Here, ultraviolet subtype-C (UVC) radiation was employed to crosslink neat poly(acrylic acid) (PAA) nanofibres and films to different crosslink densities. Specific crosslink initiators or crosslinking molecules are not necessary in this fast and simple process providing an advantage for biological applications. Scanning probe microscopy was used for the first time to measure the dry and wet dimensions of hydrogel nanofibres. The diameters of the swollen fibres decrease monotonically with increasing UVC radiation time. The fibres could be reversibly swollen/contracted by treatment with solutions of varying pH, demonstrating their potential as artificial muscles. The surprising success of UVC radiation exposure to achieve chemical crosslinks without a specific initiator molecule exploits the ultrathin dimensions of the PAA samples and will not work with relatively thick samples.
Grant Number
ARC/FF0669110
Additional Grant Number
Included in
Life Sciences Commons, Physical Sciences and Mathematics Commons, Social and Behavioral Sciences Commons
Publication Details
Gestos, A., Whitten, P. G. & Spinks, G.M. & Wallace, G. G. (2010). Crosslinking neat ultrathin films and nanofibres of pH-responsive poly(acrylic acid) by UV radiation. Soft Matter, 6 (5), 1045-1052.